The invention relates to a mechanical device that combines the function of self-locking differential and torque divider, and is designed to operate to a given ratio between two halfshafts.
Such a device is intended specifically as a master differential for vehicles with more than two drive wheels, though no limitation is implied, since the device can serve as a differential in any driveline where special requirements may dictate an unequal distribution of torque to two driven halfshafts. One of the applications envisaged for the invention is that of operation as a combined torque divider and self-locking master differential in a four-wheel drive or other multi-drive-axle vehicles, in which a fundamental requirement exists for self-locking differentials that will transmit dissimilar values of torque to different shafts. In a four-wheel drive vehicle, for instance, the load on the front and rear axles will never be distributed evenly, and to compensate, torque must be distributed to the two axles unevenly.
Attempts have been made to meet this requirement by designing torque-dividing differentials with self-locking systems, in which the typical differential action, i.e. that of enabling two halfshafts to rotate at different speeds, is either inhibited or limited according to the difference in speed or torque registering between the halfshafts. Systems of this type are generally complicated, and in the great majority of instances are capable of locking (that is, of engaging positively) only in response to a difference in speed or torque occasioned by loss of grip at the driving wheels.
Accordingly, the object of the present invention is one of eliminating the drawbacks and overcoming the limitations outlined above.